package com.itheima.reggie.filter;


import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检测用户是否登录
 */

@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {


        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1.获取uri
        String requestURI = request.getRequestURI();

        log.info("拦截到请求: {}", requestURI);

        // 不需要处理的请求路径
        String [] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login",
                "/doc.html",
                "/webjars/**",
                "/swagger-resources",
                "/v2/api-docs"
        };

        //2.判断请求是否需要处理
        boolean check = check(urls, requestURI);

        //3.不需要处理，直接放行
        if(check)
        {
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

        //4.需要处理，判断登录状态

        //4.1管理人员，已登录，继续
        if(request.getSession().getAttribute("employee") != null)
        {
            log.info("用户已登录，用户id为：{}", request.getSession().getAttribute("employee"));

            Long id = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(id);

            filterChain.doFilter(request,response);
            return;
        }
        //4.2 前端用户，已登录，继续
        if(request.getSession().getAttribute("user") != null)
        {
            log.info("前端用户已登录，用户id为：{}", request.getSession().getAttribute("user"));

            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request,response);
            return;
        }

        log.info("用户未登录");

        //5.未登录，通过输出流的方式向客户端页面响应数据
        //if (res.data.code === 0 && res.data.msg === 'NOTLOGIN') {// 返回登录页面
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));

        return;
    }

    /**
     * 本次请求是否放行
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String [] urls, String requestURI)
    {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if(match)
                return true;
        }
        return false;
    }
}
